puffiness or swelling of the eyelids or around the eyes, face, lips, or tongue

rash

restlessness

seizures

shaking

skin rash

swelling around the eyes

tightness in the chest

total body jerking

trouble with sleeping

troubled with breathing

unpleasant breath odor

vision changes

vomiting of blood

wheezing

yellow eyes or skin

Minor Side Effects

Some famotidine side effects may not need any medical attention. As your body gets used to the medicine these side effects may disappear. Your health care professional may be able to help you prevent or reduce these side effects, but do check with them if any of the following side effects continue, or if you are concerned about them:

Less common:

Difficulty having a bowel movement (stool)

Rare

Swelling of the breasts or breast soreness in both females and males

Incidence not known:

Abdominal or stomach discomfort

blemishes on the skin

change in taste or bad, unusual or unpleasant (after) taste

continuing ringing or buzzing or other unexplained noise in the ears

decreased interest in sexual intercourse

difficulty with moving

dry skin

fear

hair loss or thinning of the hair

hearing loss

hives or welts

inability to have or keep an erection

loss in sexual ability, desire, drive, or performance

mood or mental changes

muscle cramps

muscle stiffness

pimples

redness of the skin

redness of the white part of the eyes

seeing, hearing, or feeling things that are not there

sleeplessness

unable to sleep

weight loss

For Healthcare Professionals

Gastrointestinal

Gastrointestinal side effects including diarrhea (1.7%) and constipation (1.2%) have been reported. Vomiting, nausea, abdominal discomfort, anorexia, and dry mouth have been reported infrequently. Hypergastrinemia of uncertain clinical significance has also been reported.[Ref]

Nervous system

Confusion, lethargy, delirium, psychosis, agitation, seizures and somnolence have been reported, particularly in elderly patients and patients with multiple medical problems. The frequency of such reactions may be greater than previously believed. The FDA has accumulated 72 reported cases of such central nervous system reactions. All H2-blockers cross the blood-brain barrier and are found in the cerebrospinal fluid.[Ref]

Nervous system side effects have included headache (1% to 4.7%) and dizziness (1.3%). Grand mal seizures, paresthesia, and somnolence have been reported infrequently. Lethargy, confusion, psychosis, and agitation have been reported. Delirium has been reported, which reversed upon drug withdrawal. Convulsions, in patients with impaired renal function, have been reported very rarely.[Ref]

Hepatic

Hepatic side effects have included mild elevations of liver function tests. The clinical significance of these elevations is unknown. Jaundice and cholestatic jaundice have been reported infrequently. Cases of drug-induced hepatitis have also been reported.[Ref]

Cardiovascular

A 92-year-old male with a history of diabetes mellitus, hypertension, coronary artery disease, and pacemaker implantation for sick sinus syndrome experienced acquired long QT syndrome coincident with famotidine (the active ingredient contained in Pepcid Oral Suspension) therapy. The patient was admitted with fever, periurethral abscess, and enterococcal sepsis. He was treated with several medications including famotidine. He was administered famotidine at 20 mg per nasogastric tube twice a day after admission. He developed an acute myocardial infarction 10 hours after famotidine therapy. The admission 12-lead electrocardiogram revealed a ventricular paced rhythm at a rate of 60 beats/min and a QTc of 439 ms. After two 20 mg doses of famotidine, the QTc became markedly prolonged at 618 ms. Four days after famotidine was discontinued, the QTc returned close to baseline at 445 ms.[Ref]

Cardiovascular side effects have included decreases in stroke volume and cardiac output and may be clinically significant in patients with preexisting cardiac dysfunction. A variety of arrhythmias, including bradycardia, tachycardia, AV conduction defects (including AV block), and palpitations have also been reported rarely. Prolonged QT interval has been reported very rarely in patients with impaired renal function whose dose/dosing interval of famotidine may not have been adjusted appropriately.[Ref]

Renal

Renal side effects have included rare cases of interstitial nephritis.[Ref]

Endocrine

Endocrine side effects have included anti-androgen effects of reversible hyperprolactinemia and gynecomastia.[Ref]

Dermatologic

Dermatologic side effects have infrequently included alopecia, acne, pruritus, dry skin, and flushing. At least one case of contact dermatitis in a worker handling famotidine (the active ingredient contained in Pepcid Oral Suspension) has been reported.[Ref]

A 22-year-old man reported painful, erythematous macules on his chest five days after starting famotidine. These progressed to hemorrhagic, painful erosions of the oral, conjunctival, and urogenital mucosal areas. A lymphocyte transformation test (LTT) was positive indicating an antigenic response to famotidine. The lesions completely resolved in 4 weeks after stopping famotidine and administering prednisolone, tobramycin, oxacillin, cefotaxime, and fluconazole.[Ref]

Hematologic

A case report of agranulocytosis eight days after the initiation of famotidine (the active ingredient contained in Pepcid Oral Suspension) therapy has been reported in a 87-year-old male. After discontinuation of famotidine, initiation of empiric antibiotic use for the treatment of neutropenic fever, and administration of granulocyte-colony stimulating factor, the patient's white blood cell count and granulocyte count improved.[Ref]

Hematologic side effects including neutropenia have been reported. Rarely, reversible thrombocytopenia, agranulocytosis, pancytopenia, and leukopenia have been reported.[Ref]

Respiratory

Respiratory side effects including bronchospasm and interstitial pneumonia have been reported infrequently.[Ref]

Psychiatric

Psychiatric side effects including depression, anxiety, insomnia, hallucinations, and decreased libido have been reported.[Ref]

Musculoskeletal

Musculoskeletal side effects have infrequently included rhabdomyolysis, musculoskeletal pain including muscle cramps and arthralgia.[Ref]

Other

Other side effects including tinnitus, fever, asthenia, fatigue, and taste disorder have been reported infrequently. At least one case of hyperpyrexia in association with famotidine (the active ingredient contained in Pepcid Oral Suspension) use has been reported.[Ref]

Other formulations

Related treatment guides

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